"Cigar" Smoke Test

Post by **rmmagow** » 02 May 2012, 08:15

I saw a youtube thing about using a cigar for a poor man's smoke test to look for vac leaks: Think this'd work on a 98 V70 LPT? Blow through the brake vac line? I've had a long time issue with codes P0171 and P0243. I have a new MAF and thanks to jblackburn, a correctly functioning turbo boost controller. I plan to replace one at a time to see what happens but first, I know my system better not have vacuum leaks. Most hoses that are easily seen/touched seem to be fine. The shop where I bought the car had done the PVC job already and it is working correctly.

Post by **jreed** » 03 May 2012, 05:46

I haven't tried it, but it might work.
A mechanic's stethoscope might be of use to listen for whistling noises around each fitting, but I haven't tried that either.
I generally just do what you suggested already: inspect the hoses and connectors by eye, sometimes while flexing or pulling gently to look for looseness, hidden splits or cracks.
Good luck!

Post by **zulu-v40** » 03 May 2012, 06:54

I've done the cigar smoke vacuum leak test. It definitely works. It's helpful to have a shop light. You could also spray carb cleaner on the hoses, elbows, etc. while the car is running too. If there's a change in the idle, then you've got a leak.

ambishop · Post by **ambishop** » 04 May 2012, 05:21

the BEST way to do it is to get a mighty VAC. Hook it to your vacuum lines with the ignition off. Then pull a vacuum with the mighty vac. If you want to blow smoke in one of them that is an option as well. If you have a mighty vac and a mechanics stethoscope you can find anything quickly.